NEW YORK (CBSNewYork/AP) –New Jersey lawmakers announced Monday that they are intensifying their investigation into the role that politics played in lane closures to an approach to the George Washington Bridge.

A special Assembly committee is being formed that will have subpoena power and a special counsel appointed to it.

Its chairman is to be John Wisniewski, who as head of the chamber’s transportation committee launched the initial investigation into the closing of lanes leading to the GWB.

“We need to know who else in the governor’s office was involved in authorizing it,” Wisniewski said.

“As the evidence in the case has unfolded, it’s become clear the questions that need answering here are no longer just transportation questions,” said Vincent Prieto, the incoming speaker of the state Assembly. “An abuse of power like this is not something that we will stand for.”

Republicans are cooperating, for now, CBS 2’s Tony Aiello reported.

“My hope is that none of this becomes simply partisanship. If there’s wrongdoing, clearly it should be referred to the apropriate law enforcement agency,” said Assembly GOP Leader John Bramnick.

The investigation last week revealed that high-ranking officials in Gov. Chris Christie’s administration appeared to engineer lane closures at the bridge in September for political retribution against Fort Lee Mayor Mark Sokolich for not endorsing Christie for re-election.

On Sunday, Wisniewski told CBS’ “Face the Nation” there’s no evidence Christie was directly involved in the traffic tie-up, but said the governor didn’t have to know about the lane closures for them to be a crime.

“When you use the George Washington Bridge for what the emails show to be a political payback, that amounts to using public property for a private purpose or for a political purpose and that’s not legal,” Wisniewski said.

Christie said Thursday he was “embarrassed and humiliated” by the conduct of some of his staff. He said he was “blindsided” by the revelations, which he said he discovered when subpoenaed emails were released last week.

“Time for some traffic problems in Fort Lee,” Kelly wrote in August in a message to former Christie Port Authority appointee David Wildstein.

“Got it,” Wildstein replied. A few weeks later, Wildstein closed two of three lanes connecting Fort Lee to the bridge, causing crippling traffic jams in the town.

The messages do not directly implicate Christie, but they contradicted his earlier assertions that the closings were not punitive and part of a traffic study and that his staff was not involved. Christie has said he didn’t know of any plot to close the lanes.

Wisniewski said it “strains credibility” that the hands-on governor wasn’t told by senior advisers who received emails about the closings.

Politicians from both sides of the aisle took to the Sunday talk shows to debate the fallout from the traffic jams and any role Christie may have played.

Former New York City Mayor Rudy Giuliani said on ABC’s “This Week” he found Christie’s explanation “pretty darn credible” that he didn’t know what members of his inner circle were up to while he was running for re-election.

“He was in campaign mode,” Giuliani said. “You miss a lot of things. You’re not paying as much attention.”

Republican National Committee Chairman Reince Priebus told NBC’s “Meet the Press” Christie could move past the scandal and still win support from primary voters in the 2016 presidential race.

He said Christie demonstrated leadership by holding a lengthy news conference Thursday to apologize for the scandal, the most serious challenge to his political career, and to disavow any knowledge of its planning.

“America’s a forgiving people, but they’re forgiving when you take ownership, you admit mistakes, you take corrective action, and that’s what Chris Christie showed,” Priebus said.